The invention relates generally to methods of forming shells for drums which are used as percussion musical instruments from thermoplastic materials which are readily deformable at elevated temperatures which are not excessive and contemplates the use of an adhesive, such as glue, for attaching the edges of such material together after it has been heated to a temperature at which it is readily deformable by manual manipulation and which has its edges connected together by a construction which is adapted to receive an adhesive material such as glue which has a higher temperature at which it deforms than that of the plastic material. Attempts have been made to form plastic drums of clear methyl methacrylate, such as shown in Zickos U.S. Pat. No. 3,626,458. Some of such prior attempts utilized, for example, forming extruded material in pipelike form by cutting the material in pieces of various sizes for different types of drums. However, the shells shown in the Zickos Patent and the previous attempts to form drumshells of methyl methacrylate have not been successful when attempted on a production basis because the shells so formed had a tendency to warp, deform or come apart. Furthermore, it was not feasible or considered possible to form shells from such material in which an almost infinitesimal number of color designs could be accomplished by any known method or process.
In addition to transparent polymeric materials which are known as Lucite or Plexiglas, drum shells have also been made of fiberglas, but said shells have not proved to be satisfactory because of difficulties in methods of fabrication and interior surface finishing. The present inventors are not aware of any satisfactory methods which have heretofore been utilized for the successful manufacture of drum shells from thermoplastic or polymeric materials such as Lucite, Plexiglass or the like.
The advantages derived from the present invention result from a method of forming such shells from plastic material which includes the utilization of a special method which is described hereinafter.